Recently, a DVD (Digital Versatile Disc), for example, is widespread as a large-capacity, random-accessible recording medium, and so are DVD apparatus for performing various processing using a DVD.
The DVD apparatus include, e.g., DVD recorders for performing recording/playback of data such as television broadcasting programs on/from a DVD, car navigation systems for recording map information and the like on a DVD and displaying the map information, and game machines for recording a program and the like of a game and executing the program.
Note that details of DVDs are described in, e.g., a Non-Patent Document 1.    [Non-Patent Document 1] DVD Specifications for Read-Only Disc Part 3; Version 1.1 December 1997